Is pregnancy safe while on treatment for pulmonary tuberculosis?

Q:I am a 27 years old female undergoing treatment of pulmonary tuberculosis, which continues for nine months. I have already taken a treatment of eight months and now I have conceived at this stage. Only a month is left for treatment. Is pregnancy safe while on treatment for pulmonary tuberculosis?

A:The first line drugs used in the treatment of tuberculosis (isoniazid or INH, rifampicin, pyrazinamide and ethambutol) can be used in pregnancy and are not known to cause any birth defects or teratogenicity. However, there are certain anti-tuberculosis medications, which are preferably avoided in pregnancy. These include aminoglycosides such as streptomycin/ amikacin/ kanamycin (which can cause ototoxicity or damage to the hearing apparatus of the fetus or unborn baby causing congenital deafness), ethionamide and prothionamide (which are potentially teratogenic or capable of causing birth defects), capreomycin (may cause fetal nephrotoxicity or congenital deafness), levofloxacin (may cause teratogenicity). These agents (streptomycin, prothionamide/ethionamide, capreomycin, levofloxacin) are not the standard first line agents for TB treatment, and are used when standard first line agents are either ineffective due to drug resistant tuberculosis or there is need of alternative route of therapy (streptomycin which is administered parenterally either intravenous or intra-muscular route). Pyridoxine or vitamin B6 supplementation (25 mg/Kg) is recommended for pregnant or breastfeeding women taking isonazid/INH. Multivitamin preparations may contain variable amounts of vitamin and may not provide adequate supplementation.
Non-pregnant patients with TB taking the anti-tuberculosis medication rifampicin need to be reminded that the efficacy of oral contraceptives could be reduced by rifampicin, and should take advice regarding alternative forms of contraception. If pregnancy occurs while taking rifampicin, it is not an indication for termination of pregnancy. Moreover, women can breast feed normally while taking anti-tuberculosis medications.
Patients taking INH/isonazid in the peripartum period (period around the time of delivery) need to be closely monitored for liver function abnormalities because of the increased risk of hepatitis.
It is not entirely clear from the description of the medication that you have provided (“rcinex – 800 mg…, myconex800mg and lcin - 750 mg”) what is currently your anti-tuberculosis medication. Rcinex is usually a combination of rifampicin and isoniazid, Myconex is usually a combination of ethambutol and INH, whereas Lcin represents levofloxacin. As stated previously although rifampicin, INH and ethambutol are considered to be safe for use in pregnant individuals, levofloxacin should be avoided.
I suggest you inform your doctor immediately that you are pregnant so that the most appropriate treatment could be reconsidered. Your treating physician is however in a better position to appreciate the clinical circumstances and suggest the most appropriate therapy.
References:
1. MMWR 2003;52:RR-11.
2. Thorax 1998;53:536–548.